Krishna is the Prime Causes of all Causes

I'm God, You're God, But Who Is The Supreme God?

Śrī Brahma-saṁhitā 5.1

 īśvaraḥ paramaḥ kṛṣṇaḥ sac-cid-ānanda-vigrahaḥ anādir ādir govindaḥ sarva-kāraṇa-kāraṇam

Word for word:

 īśvaraḥ — the controller; paramaḥ — supreme; kṛṣṇaḥ — Lord Kṛṣṇa; sat — comprising eternal existence; cit — absolute knowledge; ānanda — and absolute bliss; vigrahaḥ — whose form; anādiḥ — without beginning; ādiḥ — the origin; govindaḥ — Lord Govinda; sarva-kāraṇa-kāraṇam — the cause of all causes.

Translation:

 Kṛṣṇa who is known as Govinda is the Supreme Godhead. He has an eternal blissful spiritual body. He is the origin of all. He has no other origin and He is the prime cause of all causes.